This invention relates in general to a vehicular seat assembly having a flexible air bag suppression sensor apparatus. More specifically, this invention relates to a spring sensor assembly of the sensor apparatus.
Vehicular air bags play an important role in restraining a seat occupant in vehicular crash situations. However, air bags designed for adequately restraining a large sized occupant may not provide optimal restraint protection for a smaller sized occupant or for a child occupying a child seat. In addition, the deployment of an air bag corresponding to an unoccupied seat represents an unnecessary repair expense.
Sensor apparatuses have been proposed for detecting whether or not a given seat is occupied. These types of sensor apparatuses act as on/off switches in controlling the deployment of a corresponding air bag. However, these types of sensor apparatuses simply address the need for preventing the deployment an air bag when the seat is unoccupied.
Other sensor apparatuses have been proposed to detect the placement of an occupant in a given seat for the purpose of suppressing the deployment of a corresponding air bag. Specifically, these types of sensor apparatuses detect whether or not the front and/or rear portions of a given seat are occupied. In situations in which only the front or only the rear portion of the seat is occupied, a sensor apparatus provides a signal for controlling the degree in which the air bag is to be suppressed during deployment. However, these sensor apparatuses do not provide a means for suppressing the air bag when both the front and rear portions of the seat are occupied.
Other sensor apparatuses have been proposed which determine the weight of an occupant based on detected variations in seat occupancy loading for providing a means of controlling the degree in which a respective air bag is to be suppressed during deployment. However, these types of sensor apparatuses require that a sensor apparatus be directly mounted to the structure of a given seat and that the sensor apparatus itself be structural. Consequently, these sensor apparatuses are relatively massive. Additionally, these sensor apparatuses are typically sensitive to physical and environmental changes that affect the repeatability of the performance of the sensor apparatus.
Other sensor apparatuses include a flexible sensor apparatus mounted to a seating face of a seat cushion. The flexible sensor apparatus includes a plurality of sensors imbedded at various locations of the vehicle seat cushion. These sensors, along with a microprocessor and an appropriate algorithm, are generally capable of detecting both the size of a passenger and the presence of an occupied child seat for the purpose of controlling the degree in which a corresponding air bag is to be suppressed during deployment. The flexible sensor apparatus offers improved reliability, as well as the advantages of being nonstructural and compact. However, the individual sensors are commonly affected by shear forces within the seat cushion, which may lead to false signals. The plurality of sensors are also difficult to install properly onto the sensor apparatus.